const _ = require('lodash')
const array = ['jack', 'tom', 'lucy', 'kate']
console.log(_.first(array))
console.log(_.last(array))
console.log(_.toUpper(_.first(array)))//洋葱式编程
console.log(_.reverse(array))
const r=_.each(array,(item,index)=>{console.log(item,index)})
console.log(r)